[perl #122715] Returning lazy lists from a start { } block results in empty list

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# New Ticket Created by  Moritz Lenz 
# Please include the string:  [perl #122715]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=122715 >


<moritz> m: my @outer = 0..3; await my $x = start { eager @outer.map:
*+1 }; say $x.result.perl
<camelia> rakudo-moar 4a7429: OUTPUT«(1, 2, 3, 4).list␤»
<moritz> m: my @outer = 0..3; await my $x = start { @outer.map: *+1 };
say $x.result.perl
<camelia> rakudo-moar 4a7429: OUTPUT«().list␤»

Same result on the JVM.

I guess this is related to the generator being scheduled on the old
thread that has already terminated, or something like this.

Anyway, it shouldn't silently swallow the contents of a lazy list.